Electrics, KVA, can someone explain this please?

[SD1too]

Originally Posted by Roverlike

Since I is current measured in Amperes and V is voltage measures in Volts, term VoltAmps is used ... If you have number of amperes from your appliance and multiply by 220V you will get one power and if you multiply by 230 you will get another power. That is the reason why it is said VoltAmps ...

Eh? I'm sorry, that is not an explanation! Watts results from the same formula in both cases so the question remains, why not use that?
This, from UK Power Networks, also brushes over any credible reason:
https://www.ukpowernetworks.co.uk/he...-kilovolt-amps

In recent years there's been a certain amount of the reinvention of the wheel. Some people have decided that terms which have been in common use for decades, if not centuries, need to be abandoned and replaced with something different which essentially has the same meaning. For example, in the electrical world, "surge" has been replaced by "inrush". It's completely unnecessary! I think that the reason is ego. Mysterious technical terms are bandied about freely by people who want to appear important and intellectually superior to everybody else. I suspect that is what's behind "volt-amps" but I will ask a friend of mine who has worked in the electrical design field all his life. It may be that my cynical view is completely wrong!

Simon

[another_clean_sheet]

Originally Posted by macafee2

This reserve, is this the start up amperage, when a motor starts it draws more current then when it is running?

macafee2

It depends if the main fuse is anti surge fuse or not

[Phil-T4]

Originally Posted by macafee2

perhaps i should just look at the main fuse, what ever that is rated at I should be able to draw, I just cant get to it for now.

62 amps seems very low, if that is the standard supply why is the main fuse a 100?

macafee2

The 100 Amp fuse holder is the safe current rating of the cut-out equipment, the actual fuse inside the holder will be 80A (older properties are 60A)

Simple put, Watts (VxI) is what your equipment draws from the supply, VA is used for sizing equipment and wiring sizes.

[SD1too]

Well my cynical view was wrong! There is a theoretical explanation.

My friend explains that the "VA" value for electrical power is used when there is a phase difference between the voltage and the current. This phenomenon is known as the "Power factor" and, for example, is present in any appliance using a motor which typically incorporate a capacitor to reduce this effect.

Furthermore in these cases the formula V x I is actually a simplification. My friend says that the actual calculation for power in an out-of-phase circuit is V x I x Cos ø (where ø is the phase difference between the voltage and current).

In conclusion Ian I'd say that in everyday life, when you are using your vacuum cleaner or Dyson, there is no need to worry about phase difference. The world seems to have managed perfectly well for over a hundred years! Where you see the term "VA" or "kVA", just think of Watts!

Simon

[Roverlike]

Originally Posted by SD1too

Well my cynical view was wrong! There is a theoretical explanation.

My friend explains that the "VA" value for electrical power is used when there is a phase difference between the voltage and the current. This phenomenon is known as the "Power factor" and, for example, is present in any appliance using a motor which typically incorporate a capacitor to reduce this effect.

Furthermore in these cases the formula V x I is actually a simplification. My friend says that the actual calculation for power in an out-of-phase circuit is V x I x Cos ø (where ø is the phase difference between the voltage and current).

In conclusion Ian I'd say that in everyday life, when you are using your vacuum cleaner or Dyson, there is no need to worry about phase difference. The world seems to have managed perfectly well for over a hundred years! Where you see the term "VA" or "kVA", just think of Watts!

Simon

Well, thank you for confirmation about what I was saying few posts above. I was merely trying to put it in simpler words. However, I will shut up now ...

[COLVERT]

Originally Posted by macafee2

This reserve, is this the start up amperage, when a motor starts it draws more current then when it is running?

macafee2

The surge happens at start up because for a split second the motor acts as a dead short until it starts to spin up.----

[macafee2]

I have been in contact with the electric network operator asked if the supply can handle a 190 amps. I have no idea if this is a silly high figure or not. 62.5 seems very low.
anyway they are willing to do a site visit and test. I think the engineer too pity on me.
Hopefully next week I will know

macafee2

[Phil-T4]

Originally Posted by macafee2

I have been in contact with the electric network operator asked if the supply can handle a 190 amps. I have no idea if this is a silly high figure or not. 62.5 seems very low.
anyway they are willing to do a site visit and test. I think the engineer too pity on me.
Hopefully next week I will know

macafee2

190Amps what on earth will you be running?

[another_clean_sheet]

Originally Posted by macafee2

I have been in contact with the electric network operator asked if the supply can handle a 190 amps. I have no idea if this is a silly high figure or not. 62.5 seems very low.
anyway they are willing to do a site visit and test. I think the engineer too pity on me.
Hopefully next week I will know

macafee2

!90 amps is approximately 45KW. Are you confusing continuos current with the switch on surge current as they are different things.
Take a simple example. When you switch on a 3KW fire the initial current surge greatly exceeds the 13 amp fuse in the plug but does not blow the fuse.
No way will a normal house consume 190 amps. That is going to cost you approximately £7 an hour.

[COLVERT]

Originally Posted by another_clean_sheet

!90 amps is approximately 45KW. Are you confusing continuous current with the switch on surge current as they are different things.
Take a simple example. When you switch on a 3KW fire the initial current surge greatly exceeds the 13 amp fuse in the plug but does not blow the fuse.
No way will a normal house consume 190 amps. That is going to cost you approximately £7 an hour.

Yikes,---£7.00 an hour.

Lets say a ten hour day. =£70.00

Seven days a week. =£490.00

52 weeks a year . =£25,480.00--------------Oh, to be so rich.